Developement of the non-invasive deep-body temperature measuring method by reflected Ultrasouna

反射式超声波无创深部体温测量方法的研制

• 批准号: 61460149
• 负责人: SAITO Masao
• 金额: $ 3.71万
• 依托单位: Inst. of Med. electronics,Faculty of Medicine,University of Tokyo.
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-61460149/
• 关键词: Ultrasound; Non-invasive temperature mcasurement; 生体温度計測; 減衰定数

Present uses of thermocouple and thermistor in measuring body temperature face many problems. For example, the problem of limited number of measured points and metastasis in hyperthermia thermometry. These problems necessitate non-invasive temperature measurement. When ultrasound propagated through biological material, its physical parameters such as attenuation and velocity vary with temperafure. Among these parameters, attenuation seems the most practical since the existing B-mode device can be used to analyze the attenuation of reflected ultrasonic signal. The purpose of this study is to show the possibility of non-invasive temperature measurement method based on the above principle.In biological tissuse, structural relaxation processes, with an appropriate distribution of relaxation times and the contribution due to viscosity, give rise to the measured attenuation coefficient. Because viscosity and relaxation processes are related to the temperature through viscosity coefficient and relaxation times at different temperature, respectively, the attenuation coefficient is a function of temperature. Consequently, the temperature will be measured indirectly by estimating attenuation coefficient parameter.For basic study, the in vitro experiments using pig livers, pig fillets, beef livers and beef muscles were investigated. The technique used to analyze the temperature dependence of attenuation cofficient is the spectral-difference method. The experimental results indicate that the temperature dependences of attenuation coefficients of liver and muscle in the temperature range of 37-46゜C are in the order of -.006 to -.011 dB/(cm.MHz.K). In vivo experiment using pig liver also shows the negative dependency. By a more accurate instrumentation and signal processing, with preliminary known characteristics of the temperature dependences of attenuation coefficients of the tissuse of interest, it is possible to measure the tissue temperature non-invasively by this method.

目前使用热电偶和热敏电阻测量体温面临许多问题。例如，热疗测温中测点数量有限和转移的问题。这些问题需要非侵入式温度测量。超声波在生物材料中传播时，其衰减和速度等物理参数随温度的变化而变化。在这些参数中，衰减似乎是最实用的，因为现有的b模装置可以用来分析反射超声信号的衰减。本研究的目的是展示基于上述原理的无创温度测量方法的可能性。在生物组织中，结构弛豫过程具有适当的弛豫时间分布和粘度的贡献，从而产生测量到的衰减系数。由于粘度和弛豫过程分别通过不同温度下的粘度系数和弛豫时间与温度相关，因此衰减系数是温度的函数。因此，通过估计衰减系数参数来间接测量温度。在基础研究方面，以猪肝、猪片、牛肝和牛肌肉为材料进行了体外实验。利用谱差法分析衰减系数的温度依赖性。实验结果表明，在37 ~ 46 C温度范围内，肝脏和肌肉的衰减系数的温度依赖性为- 0.006 ~ - 0.011 dB/(cm.MHz.K)。猪肝脏的体内实验也显示出负依赖性。通过更精确的仪器和信号处理，以及对感兴趣的组织衰减系数的温度依赖性的初步已知特征，可以通过这种方法非侵入性地测量组织温度。

项目成果

W. Benjapolakul: 日本超音波医学会第48回講演論文集. 665-666 (1986)

W. Benjapolakul：日本医学超声学会第 48 届会议论文集 665-666 (1986)。

椎名毅: 電子通信学会論文誌. J69-A. 1085-1093 (1986)

Takeshi Shiina：电子与通信工程师协会学报 J69-A 1085-1093 (1986)。

椎名毅,鈴木良次,池田研二他編: "「生体信号の計測と相関・スペクトル解析」" コロナ社, (1987)

Tsuyoshi Shiina、Ryoji Suzuki、Kenji Ikeda 等编：“生物信号的测量和相关/频谱分析”​​Coronasha，(1987)

椎名毅: 電子情報通信学会論文誌. J69-A. 19085-1093 (1986)

Takeshi Shiina：电子、信息和通信工程师学会学报 J69-A 19085-1093 (1986)。

斎藤正男: 癌と化学療法. vol13,No.4. (1986)

Masao Saito：癌症与化疗，第 13 卷，第 4 期（1986 年）。